Sanding machine



A 1941- PQT. BLOOD SANDING MACHINE Fil ed Oct. 27, 1939 2 Sheets-Sheet 1 PERLEY 'l'. BLOOD Zmnentor Cittomcg Aug. 12, 1941. P. T. BLOOD SANDING MACHINE Filed Oct. 27, 1939 2 Sheets-Sheet 2 Knventor Gtfomeg Patented Aug. 12, 1941' SANDING MACHINE Perley T. Blood, Hamilton, Mont., assignor of one-half to William A. Bower, Hamilton, Mont. Application October 2'7, 1939, Serial No. 301,627

Claims. ,(Cl. 51-170) A My present invention relates to an improved I sanding machine of the portabletype in which is employed a rotary disc driven by a powerrotor unit such as an electric motor or an air motor. Such devices are usually used for finish ing all types of'wood surfaces. It has been an inherent objection to most of the sanders that have been on the market or in use in the past that they are not adjustable as to the depth-of the finishing or sanding out which the rotary disc could take upon operation.

Another difllculty with the present portable sanders, if they were'adjustable, has been in the Figure 2 is a perspective-view of the sander from an angle at variance to that of Figure l,-

Figure 3 is a plan view of the base or housing of my sander, i

Figure 4 is 'a perspective view of the lower portion of the sander taken froman angle similar to that of Figure l with the removable edging complexity in the parts arranged to provide for adjustment.

The principal objects of this. invention are to provide a compact portable and motor-driven tool of this character that is simple in construction and operation; to provide a sanding machine composed of the minimum number of'parts that are arranged compactly into a unitary structure: to provide a sanding machine having means for adjusting the rotary disc which means are so located as to be available to the operator and so constructed as to provide adjustment without the necessity of special tools or the like: and to provide a sander which can be'easily adapted to use in restricted areas such as vertical edges whereby the sanding operation may be carried out fully to the juncture of the surface being sanded with that of an angularly disposed surface.

In my present invention I illustrate a powerrotor unit comprising an electric motor suitably supported upon a base structure and having a rotary disc mounted directly upon the shaft of the' power-rotor unit, and means are provided whereby the casing enclosing the rotary disc may be adjusted with relation to the disc for sanding in depressions and the like. -I also employ an improved base structure having guide means to insure the finishing of wood surfaces upon an absolutely true plane. e

The invention consists in certain novel combinations and arrangements of parts whichaccompany the foregoing objects and will be more fully set forth hereafter and claimed in the accompanying drawings, wherein I have illustrated a preferred form of my invention and wherein the parts are combined and arranged in accord with the best mode I have thus far devised for the practical application of the j principles of my L invention.

Figural is a perspective viewof the sander illustrating the general arrangement of parts,

relation to said bushing. The spring-receiving plate partially displaced and portions broken away for convenience of illustration,

' Figure 5 is a vertical sectional detail view taken transversely through the upper portion of the machine,

Figure 6 is a vertical sectional detail view taken transversely through the base or housing and illustrating the general arrangement of the working parts of the sander,

.Figure '1 is a fragmentary vertical sectional view through one edge of the housing and illustrating a manner in which the relation of the parts may be altered under certain circumstances, Figure 8 is a perspective view of the latch-bar used in connection with my invention,

Figure 9 is a perspective view of the latchbushing employed in the base housing in securing the removable edging plate, and

Figure 10 is a detail sectional view of the ad- Justable bearing nut which I employ in connection with my invention.

In the accompanying drawings, wherein like reference numerals refer to like parts throughout the same, the numeral ll designates a hollow base or housing having an exhaust extension II in the interior of which is formed an exhaust passage i3 and a base extension ll used to guide with the chamber f8. Apassage II in the flange- Ii communicates between the chambers Ii. v

-A removable edging-plate i 9, roughly segmental in shape, is fitted to the forward portion of the II' and base II and a lock-stud", having a notch ll, engages the bushing 22 of Figure 9, and the notch 2| aligns with a slot 23 in said bushing. The

bushing 22 extends laterrlly through wall ll of the housing and in a passage 2' I provide "the latch-bar 28 of- Figure 8, having a flange l! on its upper end and a'slot' 2t formed in its lower portion. The bushing 22 passes through the slot II and the latch-bar travels up and down with boss 29 of the lower end of the latch-bar seats against the spring 36 in the lower end of the passage 25 to keep the latch-bar normally raised to its upper position.

A motor case 3| is mounted upon the base II and is secured in place by means of screws or bolts 32, with an annular cushion 33 placed be-:

tween the two parts. A stud-bolt 34 in the base "H to hold the adjustable bearing nut in an adjusted position.

To the flanges Iii of the nut 65 I secure the adlusting cap 18-, which has a knurled or roughened depending skirt 1!! encircling the extension 64 of the lower case.

In line with the exhaust passage i3 of the base extension I 2 I mount the riser tube 80 having an Y attaching flange 8| and upon the upper end of the riser tube 80 is a nipple 82 to which is attached the dust-bag 83 for the collection of the dust particles from the material being sanded.

hand grip 38 is secured to another portion of I the case in the usual manner. In the upper face of the handle 38 I mount the switch 39 and from the lower part of the handle extends the electric conduit cord-4l|, attached by means of a plug 4|.

The motor case 3| is bell-shaped and forms the head 42. Within the interior of the case 3| I mount stationary fields 43 and 44. -By means of a suitable bearing (not shown) in the lower portion of the case and the bearing 45 in the head .42 I mount for rotation the armature shaft 46, which has the usual armature 41 and the usual commutator ring 48. Conventional brush-holders are indicated at 48 and brushes 60 are mounte'd therein for operation upon the commutator 48. Adjustment screws 5| are threaded into the brush-holders 49 for applying pressure to the brushes 50. The brushes are electrically connected to the switch 39 in the conventional manner.

Upon the lower portion of the shaft 46 I fasten the fan hub, or blower 52, which has an annular flange 53 and depending fan blades 54. At 55 the shaft 46 is threaded both interiorly and exteriorly. Upon the exterior threads is engaged the boss 58 of the rotary sander disc 51. A sander cushion 68 is secured to the lower working face of the disc 5'! and an abrading disc 59 is fitted to the face of the cushion and secured in place by means of the fiat screw 80, which engages the inner threads of the shaft portion 55.

The upper end of the armature shaft 48 isreduced in size at Si and a bearing-race 62 is fitted thereover and abuts the shoulder formed at the juncture of the shaft 6| near the shaft 46. A bearing ring 83 is mounted for rotation upon the race-'62. The head 42 of the motor case has an extension collar 84 which is interiorly threaded gor the reception of the adjustable bearing nut The bearing nut 85 is threaded around its exterior periphery and has an inner web through which is formed a passage 61. In the lower face of the web I form a bearing-race 68, and in the upper face a similar bearing race 89. The nut V has a flange 10 with notches m' in the'under face thereof. The nut 85 is threaded into the extension 64 so that the race will contact the hearing ring 83.

A second bearing ring H was placed in the up In the lower. face of the base orhousing and of the removable edging plate I form venting grooves 84, which extend radially from the lower inner edge of the sander chamber l5 and serve to permit the inward flow of air, which will pick up any dust upon the surface on which the sander is being operated, in order that the dust may be conveyed by means of the fan to the dust bag.

In the base extension I form'vent holes 85 connected by means of interior vent passages 86, that likewise communicate with the sander chamber for the conveyance of sander dust and the like in a similar manner as before described.

In operation my portable sander is placed upon the surface to be finished and by means of the switch 39 the motor is energized in the usual manner, causing the rotary sander disc to revolve at a high speed. As the disc revolves over the surface, the abrading materials on the face of the disc 59 cut the wood surface or the finish and the simultaneous rotation of the fan blades 5% creates a suction in the chamber it which picks up these particles through the .vent grooves 86 and the vent holes 85 and exhausts them into the passage l3, through the riser tube Bil, from whence they are eventually deposited in the dust bag 83.

, If it be desired that more pressure be applied upon the rotary disc 51, a turn of the bearing adjustment nut 85 causes the armature shaft 48 to be extruded downwardly and thus lowers the operating face of the disc 57 with relation to the gliding face of the base il. A reversal of this operation will result in raising the sander disc from the surface being sanded and a thinner or lighter cut would thereby be taken.

When it is desired to operate the sander closely against a surface disposed at an angle to the surface being sanded, the removable edging plate I3 is disengaged from the housing ii and the sander can then be operated to within a small fraction of an inch to the edge of the work being finished. To remove the plate I9 the pressure is applied upon the flange 21 of the latch bearing 26, thus depressing it and disengaging the lower edge of the slot 28 from the notch 2| in the stud 2B which may then be withdrawn from the bushing 22. To resecure the plate to the base H, the pin 20 is inserted into the bushing .22 so that the latch may again engage in the notch 23.

Under certain circumstances it is highly desirable to have only a portion or one edge of the rotary sander disc extrude from the casing, and in order to accomplish this, at one portion of the annular compressible cushion, I compress the material of the cushion by tightening the nut 38 on the stud-bolt M. This raises the base i and the plate l9 substantially, as shown in Figure 'I. With the device adjusted in this manner the rotary sanding disc may be operated into depressions as, for example, seat bottoms or into other cupped areas.

It to be understood that the form of my invention, herewith shown and described, is to be taken as a preferred example of the same, and

that various changes in the shape, size and arrangement of parts may be resorted to, without departing from the spirit of my-invention, or the scope of the jsubjoined claims.

Having thus fully described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A portable sander comprising a base hous-' ing having a sander chamber havinga single opening fo the reception of a sander member and adapted to completely enclose such a member and a blower chamber in communication with each other, said blower chamber having a discharge passage; an encased-powerrotor unit mounted vertically on the base housing and including a I drive shaft; a bladed fan on said shaft in said in communication with each other, said blower chamber having a discharge passage; an encased power rotor-unit mounted vertically on the base housing and including a drive shaft; a resilient cushion between said base and said power unit;

means includinga stud bolt and an adjustment nut cooperable with said bolt tor tilting said encased power rotor unit with relation to said base housing; a bladed fan on said shaft in said blower chamber; a sander disc in said sander chamber; longitudinally adjustable means ior said rotor unit comprising an adjustable bearing nut threaded in the casing of the rotor unit, bearing rings cooperating with said nut, and means on said shaft and operating on said bearing rings to rotatably mount the rotor drive shaft in said adjustable bearing nut.

3. In a portable sander of the type employing a chambered base enclosing sander means and blower means and supporting an encased vertically positioned power rotor unit, a segmental edging-plate disposed against an outer face of said chambered base-and having an inwardly protruding notched lock-stud, a slotted bushing positioned in the wall of the chambered base to receive the lock-stud, and a-latch bar cooperable with the slotted bushing and with the notched;

lock-stud to retain the edgin -Plate in position against the chambered base.

4. In a portable sander of the type employing a chambered base enclosing sander means and blower means and supporting an encased vertically positioned power rotor unit, a segmental edging plate disposed against an outer face of said chambered base and having an inwardly protruding notched lock-stud, a slotted bushing positionedin the wall of the chambered base to receive the lock-stud, and a spring pressed vertically movable latch bar cooperable with the slotted bushing and with the notched lock-stud to retainthe edgingplate in position against the chambered base.

5. In a portable sander of the type employing achambered base enclosing sander means and blower means and supportingian encased ver tically positioned power rotor unit,. a resilient cushion between said base and said power rotor unit, and means including a stud bolt and an ad.- justment nut thereon for tilting" said encased power rotor unit with relation to said base hous- I FERLEY '1". BLOOD. 

